How I can assign or impose a password to my flash drive to be open?

Question

I have a flash drive, a cheap one

Answer 1

You can download folderlock from http://www.newsoftwares.net/folderlock/
Instructions are at
http://www.newsoftwares.net/folderlock/howto/password-protect-USB-flash-drive.html

Answer 2

Don't quite understand. Do you mean you want to see the contents when you click to open?

This might do it.
USB – Open in Folder View Automatically
Source: James Coates, Chicago Tribune

You need to change a number of settings by hand for each one of your removable memory gadgets. Plug in one of them and ignore the pop-up asking what you want to do.

Instead, click open My Computer, find the listing for the removable drive you plugged in and give it a right-click.
Select Properties.
A tabbed menu will pop up including a heading for Auto Play.
A small drop-down box there includes the names of various file tuypes such as Music, Pictures, Video, etc.
Start by clicking in the circle to set an action.
Then pick each of these types in turn and move down the list of options that come up automatically for that type.
Pick Folder View for Music, and click Apply.
Move down to Pictures, select Folder View again.
Repeat for the other file types, clicking Apply each time.

This creates a file on the drive that works along the lines of autoplay.inf routines written on CDs to make them bootable.